xdp: fix zero-copy frame layout

Answer in brief

CVE-2026-81002 records a Unknown severity vulnerability in xdp: fix zero-copy frame layout. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 11, 2026Updated Sep 11, 2026Source checked Sep 12, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=b0d1beeff2a97a0cf1965ea8f1d13b8973f22582 <444216dacdbebd3e52d5e704facafbb230da09e9 \|\| >=b0d1beeff2a97a0cf1965ea8f1d13b8973f22582 <15d1f3c0dbe7a740f779337deb39f23cd8d002c8 \|\| >=b0d1beeff2a97a0cf1965ea8f1d13b8973f22582 <68d7cc5512238693670fc19c7a615df631e10edf \|\| >=b0d1beeff2a97a0cf1965ea8f1d13b8973f22582 <71283aaa6c65b3cec84caf1dc78560985737641f	444216dacdbebd3e52d5e704facafbb230da09e9, 15d1f3c0dbe7a740f779337deb39f23cd8d002c8, 68d7cc5512238693670fc19c7a615df631e10edf, 71283aaa6c65b3cec84caf1dc78560985737641f
Linux/Linuxgeneric	4.20	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 444216dacdbebd3e52d5e704facafbb230da09e9 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: xdp: fix zero-copy frame layout xdp_convert_zc_to_xdp_frame() clones an XSK packet into an order-0 page and advertises PAGE_SIZE as its frame size. It allows the copied frame to occupy the page tail needed by skb_shared_info and records zero headroom even when metadata separates the frame header from packet data. An AF_XDP zero-copy packet redirected through cpumap can therefore make the skb overlap skb_shared_info or place it beyond the allocated page. Limit the copied layout to SKB_WITH_OVERHEAD(PAGE_SIZE) and include the metadata length in frame headroom. Redirect callers already handle a NULL conversion result. BUG: KASAN: slab-out-of-bounds in skb_gro_receive Write of size 4 at addr ffff88800cf37004 by task cpumap/1/map:1/146 Call Trace: skb_gro_receive (net/core/gro.c:174) udp_gro_receive (net/ipv4/udp_offload.c:812) inet_gro_receive (net/ipv4/af_inet.c:1539) dev_gro_receive (net/core/gro.c:515) gro_receive_skb (net/core/gro.c:633) cpu_map_kthread_run (kernel/bpf/cpumap.c:395) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:164) ret_from_fork_asm (arch/x86/entry/entry_64.S:255) Kernel panic - not syncing: KASAN: panic_on_warn set ...

Quoted source text, attributed separately from HOL analysis.